YIELD AND COMPOSITION OF EDIBLE MEAT FROM MALE BROILERS AS INFLUENCED BY DIETARY PROTEIN LEVEL AND AMINO ACID SUPPLEMENTATION

Abstract

Two experiments were undertaken to investigate yield and composition of various carcass parts when male broilers were fed diets varying in level of dietary protein and methionine and lysine supplementation. Birds fed a low protein diet (16%) showed little difference in performance or carcass characteristics when compared with a similar diet supplemented with 0.17% DL-methionine. A comparison of diets containing 17, 20 and 23% dietary protein demonstrated that birds on the 17% diet had less carcass protein and more carcass fat than the higher protein diets. However, supplementation of the 17% diet with methionine and lysine resulted in weight gain and carcass composition values similar to the higher protein diets. At similar body weights, birds fed the higher levels of protein or birds fed diets supplemented with essential amino acids resulted in higher levels of carcass protein accretion. Breast meat accounted for approximately 30% of total carcass meat; however, it would contribute close to 50% of total edible carcass protein. Since breast meat makes up such a substantial portion of edible carcass protein, a reliable estimate of carcass protein deposition should be able to be made from sampling one half of the breast. Key words: Carcass composition, protein deposition, broilers